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Brown rock shrimp is the deep-water cousin of the common pink, white, and brown shrimp also found in the warm waters of the southeastern United States. It is the largest of six rock shrimp species found in this area. Rock shrimp are often called the “little shrimp with a big lobster taste.” They can easily be mistaken for a miniature lobster tail, and the texture of their meat also is similar to lobster. Most of the U.S. harvest comes from the east coast of Florida (mainly off the Cape Canaveral area).
Before the 1970s, rock shrimp were mainly captured incidentally by trawlers fishing for their cousins— the valuable pink, white, and brown shrimps—and were considered throwaway catch. Named for their rock-hard shell, rock shrimp were nearly impossible to peel and devein. In 1969, a machine was developed that could split the tough shell and devein the shrimp, helping to create a market for the species. The first major harvest of rock shrimp (1,200 pounds) was recorded in 1970 and valued at $642. In just 2 years, by 1972, landings totaled 443,035 pounds and were valued at over $258,000. In the past decade, annual landings have averaged over 3.9 million pounds, valued at an average of $4.9 million.
Rock shrimp have a short life span and, under favorable environmental conditions, can replenish their populations quickly. Although shrimp populations are fairly resilient to fishing pressure, the rock shrimp fishery can impact sensitive habitat as well as the abundance of other species, including finfish and sea turtles. Fishermen follow fishing gear requirements and other regulations to minimize the fishery’s impact on non-targeted species and bottom habitats.
Rock shrimp are found from Norfolk, Virginia, south through the Gulf of Mexico to Mexico’s Yucatan Peninsula. They mainly live on sand bottoms in water 80 to 215 feet deep, although they’ve been found in depths of 600 feet. Rock shrimp are active at night and burrow in the sand during the daytime. Larval rock shrimp grow and develop in coastal estuaries and travel back to offshore areas as they mature.
The rock shrimp’s growth and development depends on factors such as season, water temperature, population density, size, and sex. For example, they grow faster in the summer and females grow slightly faster than males. In general, juveniles grow up to 1/10 inch per month and adults grow about 1/50 inch per month. They can grow up to 6 inches in length, but most rock shrimp found in shallow waters are less than 2 inches long.
Rock shrimp, like most shrimp species, are highly productive. Females are able to reproduce when they reach about ½ to 1 inch or larger in length; males mature when they reach about ½ inch long. Rock shrimp spawn year-round in offshore waters; spawning peaks between November and January. Individual females can spawn three or more times in one season. Males and females mate, and the eggs are fertilized when the female simultaneously releases egg and sperm. Eggs hatch within 24 hours. Rock shrimp have a short life span, between 20 and 22 months.
Juvenile and adult rock shrimp feed on the ocean floor, mainly eating small bivalve mollusks and decapod crustaceans. Sheepshead, minnows, water boatmen, and insect larvae eat postlarval rock shrimp. A wide variety of species prey on juveniles and adults.
Rock shrimp look very different from the penaeid shrimp (white, pink, and brown shrimp in the same region). While rock shrimp are similar in general size and shape, they can be easily distinguished by their thick, rigid, stony shell. Their bodies are off-white to pinkish in color, with the dorsal (back) surface darker and blotched or barred with lighter shades. Their legs are red to reddish-purple and barred with white. The abdomen has deep transverse grooves and numerous nodules. Short hairs cover their body and appendages. Their eyes are large and deeply pigmented.
Abundance estimates are not as meaningful for shrimp management as they are for management of most other seafood species. Rock shrimp reproduce at high rates and have a short life span. The abundance of rock shrimp is primarily influenced by environmental conditions and available habitat rather than catch rates. Scientists and managers monitor the status of the resource by collecting data on historic harvests and catch rates.
Adults spawn offshore and currents transport their offspring to coastal estuaries. The survival of the offspring is highly dependent on environmental conditions within estuaries. For example, excessively cold winters or heavy rains that reduce salinity may reduce survival rates of offspring.
Although shrimp trawling temporarily reduces population size during shrimp season, the impact of fishing on future populations is unknown but is thought to be minimal. Habitat loss due to pollution or physical alteration are potential threats to shrimp populations.
Commercial fishermen harvest rock shrimp using trawls. Shrimp trawlers tow cone-shaped nets along the ocean floor. The nets are wide in the front and taper toward the back, where the captured shrimp and any incidentally caught species are concentrated. Rock shrimp are caught in deeper water than penaeid shrimp (white, pink, and brown shrimp in the same region).
Who’s in charge? NOAA Fisheries and the South Atlantic Fishery Management Council
Current management:
South Atlantic: Shrimp Fishery Management Plan
Gulf of Mexico: Rock shrimp are occasionally caught in the Gulf of Mexico but not in quantities large enough to warrant specific management measures.
Annual landings vary greatly from year to year and have averaged nearly 3.94 million pounds per year in the past decade. Commercial fishermen harvested over 2.1 million pounds of rock shrimp in 2010, mainly off the east and west coasts of Florida.
In the past decade, U.S. commercial harvests of rock shrimp have been valued at an average of $4.9 million. The 2010 domestic harvest was worth a little over $2.9 million. Rock shrimp is also harvested in Mexican fisheries.
Rock shrimp gets its name from its rock-hard shell, which actually limited its marketability until a machine was developed that could split the tough shell and devein the shrimp. Because rock shrimp are so hard for people to peel, almost all the harvest is sold as meats. Rock shrimp are generally small; the largest size measures 21 to 25 shrimp per pound. Raw rock shrimp is transparent or clear white, with fine pinkish or purple lines. Rock shrimp has a firm texture and sweet, succulent flavor, similar to lobster. (Seafood Business, 2011)
Year-round with peak catches from July through October
Rock shrimp are an excellent source of selenium and vitamin B12 and a good source of iron, niacin, and phosphorus.
Servings | 1 |
Serving Weight | 114 g (raw) |
Calories | 110 |
Protein | 21 g |
Fat, total | 1 g |
Saturated fatty acids, total | 0.5 g |
Carbohydrate | 0 g |
Sugars, total | 0 g |
Fiber, total dietary | 0 g |
Cholesterol | 140 mcg |
Selenium | 38 mcg |
Sodium | 380 mg |
Brown Rock Shrimp Table of Nutrition
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